Source code for graphene.types.argument
from collections import OrderedDict
from itertools import chain
from .dynamic import Dynamic
from .mountedtype import MountedType
from .structures import NonNull
from .utils import get_type
[docs]class Argument(MountedType):
"""
Makes an Argument available on a Field in the GraphQL schema.
Arguments will be parsed and provided to resolver methods for fields as keyword arguments.
All ``arg`` and ``**extra_args`` for a ``graphene.Field`` are implicitly mounted as Argument
using the below parameters.
.. code:: python
from graphene import String, Boolean, Argument
age = String(
# Boolean implicitly mounted as Argument
dog_years=Boolean(description="convert to dog years"),
# Boolean explicitly mounted as Argument
decades=Argument(Boolean, default_value=False),
)
args:
type (class for a graphene.UnmountedType): must be a class (not an instance) of an
unmounted graphene type (ex. scalar or object) which is used for the type of this
argument in the GraphQL schema.
required (bool): indicates this argument as not null in the graphql scehma. Same behavior
as graphene.NonNull. Default False.
name (str): the name of the GraphQL argument. Defaults to parameter name.
description (str): the description of the GraphQL argument in the schema.
default_value (Any): The value to be provided if the user does not set this argument in
the operation.
"""
def __init__(
self,
type,
default_value=None,
description=None,
name=None,
required=False,
_creation_counter=None,
):
super(Argument, self).__init__(_creation_counter=_creation_counter)
if required:
type = NonNull(type)
self.name = name
self._type = type
self.default_value = default_value
self.description = description
@property
def type(self):
return get_type(self._type)
def __eq__(self, other):
return isinstance(other, Argument) and (
self.name == other.name
and self.type == other.type
and self.default_value == other.default_value
and self.description == other.description
)
def to_arguments(args, extra_args=None):
from .unmountedtype import UnmountedType
from .field import Field
from .inputfield import InputField
if extra_args:
extra_args = sorted(extra_args.items(), key=lambda f: f[1])
else:
extra_args = []
iter_arguments = chain(args.items(), extra_args)
arguments = OrderedDict()
for default_name, arg in iter_arguments:
if isinstance(arg, Dynamic):
arg = arg.get_type()
if arg is None:
# If the Dynamic type returned None
# then we skip the Argument
continue
if isinstance(arg, UnmountedType):
arg = Argument.mounted(arg)
if isinstance(arg, (InputField, Field)):
raise ValueError(
"Expected {} to be Argument, but received {}. Try using Argument({}).".format(
default_name, type(arg).__name__, arg.type
)
)
if not isinstance(arg, Argument):
raise ValueError('Unknown argument "{}".'.format(default_name))
arg_name = default_name or arg.name
assert (
arg_name not in arguments
), 'More than one Argument have same name "{}".'.format(arg_name)
arguments[arg_name] = arg
return arguments